Production of azo dyestuffs



Patented Jan. 28, 1936 UNITED STATES PRODUCTION OF AZO DYEs'rU'F'F York, N. Y., a corporation of Delaware No Drawing. Application April 2, 1935, Serial No. 14,224. In Germany April 11, 1934 4 Claims.

The present invention relates to a process of producing azo dyestuffs containing metals.

For the preparation of azo dyestufis containing metals from azo dyestufis capable of forming complex metal compounds, the chlorides, fluorides, sulphates, formates and acetates of metals capable of forming such complex compounds have usually been employed hitherto.

We have now found that azo dyestufl s containing metals are obtained in a considerably more simple manner by causing salts of halogensubstituted low molecular fatty acids with metals capable of forming complexes to act on azo dyestufis which are capable of forming complex metal compounds. According to this invention, the

preparation of the metal compounds of the 2.20

dyestufis proceeds in a short time and in a very smooth and advantageous manner. The metal compounds formed have an especially high levelling power and a good fastness to washing.

Suitable metal salts of the said kindare for example chromium and copper salts of monochloracetic acid, monobromacetic acid, dichloracetic acid, beta-chlorpropionic acid or of mixtures, such as monoacetic and dichloracetic acids or the acid mixture remaining in the preparation of chloracetic acid. Mixtures of salts of halogensubstituted lower fatty acids with other agents supplying metals may also be employed.

The following examples will further illustrate how the said invention may be carried out in practice, but the invention is not restricted to these examples.

Example 1 Example 2 0.1 molecular proportion in grams of the ortho-hydroxy dyestufi derived from 1-amino-2- hydroxynaphthalene-4-sulphonic acid and 1- phenyl-3-methyl-5-pyrazolone is dissolved in about 1 liter of water and heated for three hours at C. in a pressure-tight vessel with 10 grams of chromium oxide and 50 grams of the acid mixture remaining in the preparation of chloracetic acid. The resulting mixture is filtered by suction, and the resulting dyestuff converted into its sodium salt and then salted out. Pure rose shades are obtained on wool.

Example 3 0.1 molecular proportion in grams of the ortho alkoxyazo dyestufi derived from l-meth'oxy-Z- amin0-4-ch10r-5-nitrobenzene and 1-hydroxynaphthalene-4,8-disulphonic acid is dissolved in about 1 liter of water, 10 grams of chromium oxide and 20 grams of monochloracetic acid are added and the whole is heated for three hours at about C. The dyestufi is salted out and dried. Navy-blue shades which are very fast to light are obtained on Wool.

Eaample 4 0.1 molecular proportion in grams of the 9.20 dyestuff derived from Z-aminobenzoic acid and 1-phenyl-3-methyl-5-pyrazolone is suspended in 1.5 liters of water, 8 grams of chromium oxide and 30 grams of monochloracetic acid are added and the whole heated for seven hours at C. The dyestufi is then filtered off by suction and dried. It dyes cellulose ester or ether lacquers golden yellow shades which are very fast to light.

Example 5 About 0.1 molecular proportion in grams of the ortho-alkoxyazo dyestufi derived from diazotized 1-methoxy-4-chlor-2-aminobenzene and 2 -hydroxynaphthalene-6, 8-disulphonic acid is dissolved in about 1 liter of water, 10 grams of chromium oxide and 40 grams of monochloracetic acid are added and the whole is boiled for 24 hours under reflux. The dyestuff is then separated in the usual manner. It dyes wool pure violet shades. Instead of monochloracetic acid monobromacetic acid or beta-chlorpropionic acid may be employed.

Example 6 0.1 molecular proportion in grams of the orthoalkoxyazo dyestufi derived from diazotized 1- methoxy-2-aminobenzene-4-sulphonic acid benzyl ester and Z-hydroxynaphthalene-G, 8-disulphonic acid is dissolved in about 800 cubic centimeters of water, 10 grams of chromium oxide and 40 grams of monochloracetic acid are added and the whole is boiled for 18 hours under reflux.

The solution is then worked up in the usual man 55 o a "tai'ning' chromium which comprises caue ing salts cf'halogen-osubstituted low molecular fasty'acids 1 with chromium "so act on'azo dyestuffs which are I capable of forming complex metalf'compounds; V

' ner. The dyestilff thuspbtaineci dyes wool clear Bordeaux-red shades. V 1

What-we claim is:-'-

" '1, A process bf i producing halogen-substituted low molecular fatpy" acid with imeftalsicapable of; forming complexes to acton azoidyestufis j which" are capable of forming complex'metal compounds.

.2, A7process of producing azo dyestgff cori- $2,028,981 I a V V v 3, 3 proces s ofproducing azo dyestuffsprgtainiiag metals which comprises causing "salts of j monochloracetic acid. with metals capable of V L forming complexes'to act on azo dyesufis which,

azo dyestu ffs con V i I V are capable-of forming complex metal comtaming metals which comprises causing' salts of pounds.

7 "4; 'A process iof producingaaodxesbufis con- 'tainifig' meta-Is'which comprises causingsaltslof T p V dichloracetic acid with metals capable of forming complexes to act on' azp dyestuffs; which are is. capable of 'formi ng complex metalcom'pohnda o 

